My story with Huntington's disease began about ten years ago. Unfortunately, it's a sneaky disease that affects each individual in a different way, so it was not easy to recognize it and give it a name until you get the result of the genetic test.
To date, I known many people with this disease, including my wife, who had a father, grandmother and aunt with Huntington's disease. I learned many things by living with them, such as patience, understanding, and happiness in appreciating every single moment in which the disease goes into 'stand by'. People with Huntington's disease cannot take long walks or go for bicycle tours, in short, life changes and even daily gestures such as eating, traveling, dressing can become challenging.
I feel like giving you some advice: the most beautiful thing you can do for them is to accept the pathology and adapt your daily life consequently.
Make them feel autonomous, indispensable, encourage them and not pity them! Stay close to them to help them get things right; never demonize or admonish them for something they are unable to do.
In short, the key of living with a sick person is love. And the winning weapon against the depression that chases them is hope in science, because without these two small precautions they would be alone and lost in a society that responds very little to their real needs. So love them, support them, cuddle them; by doing this the disease, almost by magic, will be less painful also for you.